Cognitive well-being in classrooms: A holistic investigation into Indoor Environmental Quality in New Zealand primary schools

Children spend about 80-90% of their time indoors, making the quality of indoor environments (IEQ) crucial, particularly since children are more susceptible to pollutants due to their developing bodies and higher relative air intake per body weight. This study examines the influence of various indoor environmental conditions on cognitive performance in primary school students. Data collected over the first three weeks from a total eight-week cognitive study are analysed, focusing on the impact of thermal comfort and CO2 levels as proxies for ventilation. 
Classroom environments were categorised into three conditions: ‘TEST 1’ (moderate CO2, temperature, and humidity), ‘TEST 2’ (elevated CO2, optimal temperature), and ‘TEST 3’ (higher CO2 and temperature). The findings are based on Shapiro-Wilk normality tests, linear regression, ANOVA, and Kruskal-Wallis tests across three cohorts (RM5, RM6, RM7). Results show that ‘TEST 1’ conditions generally support standard cognitive performance, while ‘TEST 3’ conditions, characterised by elevated CO2 and temperature, negatively impact working memory and attention. ‘TEST 2’ conditions present mixed results, suggesting that even minor changes in environmental factors can influence cognitive outcomes.  
Overall, the study highlights the necessity of maintaining optimal indoor environments to support cognitive functions and academic performance. Sensitivity to environmental conditions varies among cohorts, indicating that personalised approaches to environmental management may be required to optimise learning conditions.